This invention relates to a composition containing an isothiocyanate, and labels, sheets and packages made of the composition.
Isothiocyanates, which are contained in mustard and wasabi, are known to have antibacterial and antifungus functions. Isothiocyanates reveal their effects even in a small amount. But since they are highly volatile, release control is necessary to sustain their effects.
Japanese patent publication 2000-343640 discloses a method of manufacturing a volatile agent release control film in which an isothiocyanate is dissolved in an adhesive, and the solution obtained is applied to a volatile agent non-permeable film and another volatile agent permeable film is laminated to the applied surface.
But with such a laminated sheet, bleeding of the adhesive may occur from its cut surface. If the selection of a resin forming the film is improper, the adhesion strength tends to decrease as the isothiocyanate volatilizes, so that peeling can occur. Also, if the amount of the isothiocyanate is excessive, the resin may plasticize, so that the adhesion strength may decrease. Further, if the hardness at cut surfaces of the composition in the label or laminated sheet is improper, the composition may bleed from the cut surface or blocking may occur.
An object of this invention is to provide a resin composition in which bleeding of the adhesive is suppressed, and the adhesion strength is retained even after the isothiocyanate has volatilized.